post method
Issues an HTTP POST request to the specified URL, returning a Promise that resolves with an {@link @microsoft/signalr.HttpResponse} representing the result.
url: The URL for the request. options: Additional options to configure the request. The 'url' field in this object will be overridden by the url parameter. Returns a Future that resolves with an describing the response, or rejects with an Error indicating a failure.
Implementation
Future<SignalRHttpResponse> post(String? url,
{required SignalRHttpRequest options}) {
options.method = 'POST';
options.url = url;
return send(options);
}